Long draft cradle



Oct. 2, 1962 W. MACDONALD LONG DRAFT CRADLE Filed April 19, 1960 INV ENT OR 11%2725? NWCOO/VALQ,

[5AM dHh-g M I BY W. AIIORNEYS rates donald and Sons Inc, Seekonlr, Mass, a corporation of Rhode Island Filed Apr. 19, 1961, S91. No. 104,143 9 Claims. c1. 19-255 This invention relates to improvements in long draft cradles of the character used to support the endless belts or aprons that are used as parts of long draft spinning mechanisms.

Cradles of this character, as used for a long time heretofore, have been made of steel or other metals, but these are subject to many objections in service and in manufacture, which make them undesirable. Attempts have been made to correct these objections by the use of plastic inserts fitted to the side plates of the cradle, but these also have not solved all of the problems involved. It has also been suggested that the side plates of the cradles be formed of plastic materials with metal connecting bars extending between the side plates. Due to the structure thereof, these have been objectionable because of the expense and time required for construction and maintenance and by reason of the collection of lint and fibers in the cradle during operation.

One object of this invention is to overcome these objections and to improve the construction of the cradle. Another object of the invention is to provide a cradle of non-metallic or plastic material which may be manufactured and used at relatively low cost and which assures of cleanliness in service with little possibility of collecting lint.

These objects may be accomplished, according to one embodiment of the invention, by providing a cradle formed substantially entirely of substantially rigid nonmetallic or plastic materials, in two main parts. These comprise side plates, each of which has inward projections thereon extending inwardly a sufficient distance, so that when these are assembled, the projections are disposed in abutting relation with each other and may be connected through pins or other fastenings in a monolithic assembly. Guide ribs are also formed in one integral piece with the side plates, to guide the yarn and prevent it from exceeding its proper maximum traverse. Both the ribs and the projections are blended into the side plates with rounded corners in such relation that there is no substantial collection of lint or fibers thereon during use of the cradle.

This embodiment of the invention is illustrated in the accompanying drawings, in which:

FIG. 1 is a diagrammatic side elevation of a portion of a spinning frame, showing the cradle applied to the roll shafts thereof;

FIG. 2 is a side elevation of the cradle on an enlarged scale;

FIG. 3 is a view at right angles to FIG. 2; and

FIG. 4 is a detail, partially in section and partly in elevation and showing a modification of structure.

In a conventional spinning frame to which this invention may be applied, a series of pairs of roll shafts are mounted for passage of a yarn Y therebetween in the manner illustrated in FIG. 1. These roll shafts are suitably supported on a roll stand (not illustrated) with top and bottom back rolls 1 and 2, intermediate rolls 3 and 4 and front rolls 5 and 6. The lower rolls 2, 4 and 6 usually are mounted in bearings supported in the roll stand, and these rolls are positively driven in pre-determined speed relation. The upper rolls 1, 3 and 5 rest on the lower rolls 2, 4 and 6, with the yarn Y passing between the upper and lower rolls, as illustrated.

The yarn also passes between a pair of aprons 7 and 8 ice extending over the intermediate rolls 3 and 4 and in parallel runs in tangent relation from the adjacent faces of the intermediate rolls to guide members 9 and 1d at the delivery end of the cradle.

The aprons 7 and 8 are held in place, and the intermediate rolls 3 and 4 properly disposed, by means of a cradle, generally indicated at 11 in FIG. 1. The construction of the cradle is shown more in detail in FIGS. 2 and 3.

In the embodiment illustrated, the cradle comprises a pair of side plates 12 and 13 disposed in properly spaced relation, as shown in FIG. 3, so as to receive the aprons 7 and 8 therebetween. The plates 12 and 13 are substantially identical in shape, being formed as illustrated in FIG. 2.

On the inner faces of the side plates 12 and 13 are projections 14 and 15 formed in one integral piece with the side plates and extending inwardly toward each other. The length of the projections 14 and 15 is such that they can be arranged in abutting relation end-t.o-end, and together form a spacer between the side plates, holding them properly spaced apart. A connecting member, such as a rod 16, extends through holes formed in the side plates 12 and 13 and in the projections 14 and 15, to secure the projections in proper alignment with each other and to hold the parts properly assembled.

Projections are also formed at 17 and 18 at one edge of the plates 12 and 13, disposed in alignment with each other and of a length to abut, as shown in FIG. 3, and thereby properly space the plates. These projections 17 and 18 are also formed in one integral piece with the side plates. A connecting member, such as a rod 19, extends through holes formed in the projections 17 and 1% continuously from the outside face of one side plate to the outside face of the other side plate and secures the parts together in proper spaced relation to each other.

The projections 1415 and 1718 form spacers or posts between the respective side plates. These spacers or posts are disposed on opposite sides of the notches 23, and hold the posts in a composite assembly.

The projections 17 and 18 are formed with a substantially flat top surface 2%), so as to constitute a roving deflecting table over which the yarn Y passes and to prevent the yarn from being deflected under the bottom roll 4.

Also formed on the inner faces of the side plates 12 and 13 in one integral piece therewith are ribs 21 and 22 to act as a yarn guide and to prevent the yarn from exceeding its proper maximum traverse. These yarn-guides 21 and 22 are blended in with the table 20 and also with the projections 17 and 18.

The side plates 12 and 13 are provided with upwardly concave recesses or bottom notches 23 and with downwardly concave recesses or top notches 24 separated by narrow connecting portions 25. The portions 25 extend between reduced portions of the rolls 3 and 4 when the cradle is in place and with the rolls 3 and 4 received within the notches 23 and 24.

At the intermediate portions of the front margins of the side plates 12 and 13, recesses 26 are formed in the side plates between the body of each plate and an outwardly projecting lug 27, so as to receive therein and to hold in place the guide members 9 and 10.

The holes through which the connecting rods 16 and 19 extend preferably are formed slightly smaller in diameter than the diameter of each of these rods, thus providing an interference fit between the rods and the holes in the assembled structure. This may be effective and sufficient to provide a secure monolithic construction of the parts when properly assembled.

However, if desired, each of these connecting rods may be formed as illustrated in FIG. 4, Where the rod is shown at 16 and is provided with a groove 28 in each end portion thereof in position to receive a ring, indicated at 2?,

a) formed in one integral piece with each of the respective side plates 12 and 13, so that the molded rings 29 would look in the grooves 28 in the connecting rods or pins 16'. In this event, the force fit or interference fit between the connecting rod and hole would not be necessary, and these could be held in place by the rings and grooves, as described and as illustrated in FIG. 4.

The parts of the cradle, except the connecting rods or pins 16 and 19, preferably are formed of a suitable substantially rigid non-metallic material such, for example, as any of the many thermosetting plastics. I have found that a material called Delrin is desirable for this purpose, because it has no cold flow and is relatively rigid. The cradle should be made just as rigid as possible, to preserve its perfect alignment.

The cradle is made in two main parts, which are subsequently assembled. The formation of these parts may be by injection molding, compression molding, die casting, or even sand casting. One part comprises the side plate 1.2, with the projections 14, 17 and 21 thereon, and the other part comprises the side plate 13, with the projections 15, i8 and 22. These are brought into side-byside relation with the projections 14 and 15 and the projections 117 and 18 in alignment with each other and in abutting relation, whereupon the insertion of the connecting rods or pins 16 and 19 in tight fitted relation to these projections will secure the parts in a monolithic assembly. This assembling operation does not require special dimpling tools, aligning tures, etc., and thereby effects a material saving in manufacture, as well as in service.

This construction has the following advantages over other cradles in manufacture and service:

(1) It eliminates all perishable tooling and the maintenance thereof.

(2) It eliminates the use of precision assembly fixtures and the maintenance thereof.

(3) It reduces the time required to assemble to a minimum.

(4) Unskilled labor can be used for the assembling operation.

(5) It assures greater cleanliness and less possibilities of collecting lint.

(6) Its monolithic design results in lower manufacturing cost and thereby a lower cost to the mill.

(7) Its lighter Weight reduces shipping costs.

While the invention has been illustrated and described in one embodiment, it is recognized that variations and changes may be made therein, without departing from the invention as set forth in the claims.

I claim:

1. A cradle for long-draft spinning aprons comprising side plates adapted to be applied to intermediate spinning rolls, and means connecting said side plates together comprising projections extending inwardly from the respective side plates into opposed abutting relation and formed in one integral piece with the respective side plates.

2. A cradle for long-draft spinning aprons comprising side plates adapted to be applied to intermediate spinning rolls, and means connecting said side plates together comprising projections extending inwardly from the respective side plates into opposed abutting relation and formed in one integral piece with the respective side plates, and a connecting member extending through the opposed projections and fixed rigidly thereto.

3. A cradle for long-draft spinning aprons comprising side plates having bottom notches therein adapted to accommodate a lower intermediate spinning roll, projections extending from the respective side plates and formed in one integral piece therewith, said projections being disposed on each opposite side of the bottom notch, the projections on each side of the notch being aligned in abutting relation and connected together.

4. A cradle for long-draft spinning aprons comprising side plates having bottom notches therein adapted to accommodate a lower intermediate spinning roll, projections extending from the respective side plates and formed in one integral piece therewith, said projections being disposed on each opposite side of the bottom notch, the projections on each side of the notch being aligned in abutting relation, and a connecting member extending through the aligned projections and fixed thereto.

5. A cradle for long-draft spinning aprons comprising side plates having bottom notches therein adapted to accommodate a lower intermediate spinning roll, projections extending from the respective side plates and formed in one integral piece therewith, said projections being disposed on each opposite side of the bottom notch, the projections on each side of the notch being aligned in abutting relation and connected together, said side plates and projections being formed of substantially rigid nonmetallic material.

6. A cradle for long-draft spinning aprons comprising side plates formed of substantially rigid nonmetallic material and having bottom notches therein adapted to accommodate a lower intermediate spinning roll, spacer posts between the side plates on each opposite side of the bottom notches, each post including projections extending inwardly from the respective side plates and formed in one integral piece therewith, said projections of each post being aligned and having; inner ends thereof in abutting relation, and a connecting member extending through the aligned projections of each post and fixed with respect thereto.

7. A cradle for long-draft spinning aprons comprising side plates formed of substantially rigid non-metallic material and having bottom notches therein adapted to accommodate a lower intermediate spinning roll, spacer posts between the side plates on each opposite side of the bottom notches, each post including projections extending inwardly from the respective side plates and formed in one integral piece therewith, said projections of each post being aligned and having; inner ends thereof in abutting relation, and a connecting member extending through the aligned projections of each post and fixed with respect thereto, each of the side plates having an upright rib on the inner surface thereof adjacent one of the spacer posts for guiding yarn therebetween, said ribs being formed in one integral piece with the respective side plates.

8. A cradle for long-draft spinning aprons comprising side plates formed of plastic material and having bottom notches therein adapted to accommodate a lower intermediate spinning roll, spacer posts between the side plates on each opposite side of the bottom notches, each post including projections extending inwardly from the respective side plates and formed in one integral piece therewith, said projections of each post being aligned and having; inner ends thereof in abutting relation, and a connecting rod extending through the aligned projections of each post and fixed with respect thereto, one of the spacer posts having a flat top surface forming a roving table, each of the side plates having an upright rib on the inner surface thereof adjacent said roving table for guiding yarn therebetween, said ribs being formed in one integral piece with the respective side plates.

9. A cradle for long-draft spinning aprons comprising side plates formed of a plastic material and adapted to be applied to intermediate spinning rolls, posts formed of plastic material and extending between the side plates forming a spacer therebetween and holding the plates spaced apart, and a connecting member extending through each post and fixed at its opposite ends to the side plates.

References Cited in the file of this patent UNITED STATES PATENTS 2,027,211 Thomas et a1. Jan. 7, 1936 2,944,300 Swanson July 12, 1960 

